Design
(1/3) Appeal - Timmy is probably the only one interested in this card, because big mana = big play. Johnny and Spike are upset this was in their rare slot.
(2/3) Elegance - It's a little tough to get on first read, but not too bad.
Development
(1/3) Viability - The card is definitely black, but I don't know if I understand the kicker colors. How do blue and red fight in to the flavor of the card overall? I'm just a bit lost. Additionally, it doesn't do anything crazy; it's a lot of mana for a small effect. Should have made this an uncommon at least, because if I'm pulling this for my rare, I'm gonna be upset. See Balance.
(1/3) Balance - This card suffers from... overbalancing. You're spending 4 mana (2B, 1 any and a kicker) to remove a single 1 power creature on your opponent's board. While this has niche applications (removing
Emry, Lurker of the Loch in modern,
Drannith Magistrate in commander, or
Sai, Master Thopterist whenever he shows his grubby little 'stache), not many of the things you're removing couldn't also be taken out with a
Lightning Bolt. Overall, neat idea, but the cost-effectiveness is certainly not worth a rare slot and it won't be given a second glance in many competitive circles. Does it get better the more mana you spend? Yeah, sure. But so much mana to only get rid of two threats is underwhelming. On a side note, the stats are also too small for how much you need to spend on it to make it effective. At least make him a 3/3, but a 4/4 might be nicer.
Creativity
(3/3) Uniqueness - I can't say this isn't unique. A
Behold the Unspeakable-esque ability mixed with
Twisted Image stapled onto a creature is not something I thought I'd see.
(2.5/3) Flavor - I can see it working out, a warlock hunting in the middle of the night, turning opponents' strengths into their weaknesses by sculpting their flesh in horrible ways. It took me a while to get there, but I like the image.
Polish
(3/3) Quality - Seems alright on this point. I'm not entirely certain on the order of keywords (Spend only..., Kicker, Flash), but I'm going to assume you got them right.
(2/2) Main Challenge - It fits, though I still don't see how the red or blue fits.
Subchallenges - N/A
Total: 17.5/23
The design overall is very interesting, though in my opinion the power is not worth a rare slot. If rated an uncommon or common, my evaluation might've been higher.